KR102407676B1 - Leakage detection system and method based on hydraulic head analysis - Google Patents

Abstract

The present invention relates to a leak detection system and method based on dynamic head analysis for estimating a leak section based on a point where the dynamic head change rapidly changes by monitoring the change in the dynamic head according to the measured water pressure, and the pressure head according to the water pressure Analyze the hydraulic head calculated according to the location head according to the ground height and the ground level by section, and select a leak suspect area according to the distribution of the dynamic head obtained for each node or the distribution of the change in the amount of change in the dynamic head obtained for each section, and the change in the hydrohead head fluctuates the most The section in which the maximum hydrodynamic head change is shown at the junction is estimated as the leaking section.

Description

Leakage detection system and method based on hydraulic head analysis

The present invention relates to a leak detection system and method based on dynamic head analysis for estimating a leak section from a point at which the dynamic head change rapidly changes by monitoring the change in the dynamic head for each section according to the measured water pressure.

In order to efficiently operate the water supply network, the water supply network is divided into large blocks, medium blocks and small blocks. According to this, the area where water is supplied from the water purification plant through multiple drainage basins is called a large block, and the area where water is supplied through a drainage branch pipe branched from the main drainage pipe connected to each drainage basin is called a medium block, and finally to consumers through the drainage pipe. The water supply area is called a small block.

In addition, the flow rate of water supplied from the water purification plant, the flow rate of water supplied from the reservoir, and the flow rate of water supplied to each small block through the drainage pipe are measured with a flow meter, and the water pressure is measured with a water pressure gauge at an appropriate location. In addition, according to the results of pipe network analysis, various information including the measured flow rate and water pressure, the ground height of the flow meter and hydraulic pressure gauge, pipe length, inner diameter, and pipe network data including the pipe friction loss coefficient (or roughness coefficient), etc. operate and manage

Here, although a grid-type pipe network is preferable, the small block may be formed of a dendritic pipe network, and a pressurization field (or pump) or a pressure reducing valve may be installed on the injection pipe (reservoir pipe) for supplying water to the small block for equal water pressure management.

As a method of detecting a leak suspicious section in such a small block, there is a method using a change in flow rate that appears during leaks. However, it is difficult to use a method using a flow rate change by installing only a hydraulic pressure gauge in the small block and installing a flow meter in a limited manner, and as disclosed in Patent Registration No. 10-1105192, pipe network analysis It can be used as a method to obtain it, but it cannot be used for a pipe network in which the pipe network data is not sufficiently secured because the pipe network data must be known.

As another method, as described in Patent Registration No. 10-1876730, there is a method that uses a phenomenon in which the water pressure is momentarily lowered from the normal water pressure when a water leak occurs. have.

As described in Korean Patent Registration No. 10-1876730, as a method of finding a suspected leak location among the detected leak suspicious sections, there is a method using the arrival time difference of the leak sound detected by a vibration sensor or an acoustic sensor in at least two places. However, the distance that can detect the leak sound is very limited, so it can be used only by narrowing the installation interval of the leak sound sensor. error may occur greatly, so it is difficult to use it effectively in practice.

KR 10-1105192 B1 2012.01.05. KR 10-1876730 B1 2018.07.04.

Therefore, the object of the present invention is to detect the leaking section without omission according to the measurement result of the water pressure even if the flow rate according to the leak is not calculated, and to measure the leak sound to detect the location of the leak. It is to provide a leak detection system and method based on hydrodynamic analysis.

In order to achieve the above object, the present invention includes a plurality of measuring units 10 installed along a pipeline to measure water pressure with a water pressure sensor 11, respectively; and a water leak detection unit 100 for detecting a water leak in the equal water pressure zone 2; in the water leak detection system based on hydrodynamic head analysis comprising a, the water leak detection unit 100 measures water pressure by the measuring unit 10 a data storage unit 110 for storing the position head for each node with the position as the node; a dynamic head calculating unit 120 for calculating the dynamic head for each node with the pressure head according to the measured water pressure and the stored position head; a dynamic head change amount estimating unit 130 for calculating a dynamic head change amount between both nodes of the section for each section divided by nodes; The uniform water pressure area (2), in which the distribution of dynamic head calculated for each node is outside the preset range, is selected as a leak suspect area, and within the uniform water pressure area (2) selected as the leak suspect area, the change in the dynamic head fluctuates the most. and a leak section detection unit 140 that selects a node as an inflection point and estimates a section having a relatively large amount of hydrodynamic head change among sections following the inflection point as a leak section.

According to an embodiment of the present invention, the leak section detection unit 140 selects an equal water pressure zone 2 in which the distribution of the amount of change in the hydrodynamic head calculated for each section is out of a preset range as the leak suspect zone.

According to an embodiment of the present invention, the hydraulic head change amount calculating unit 130 applies the difference in the hydraulic head between both nodes of the section and the hydraulic gradient obtained according to the pipe length of the section as the amount of change in the dynamic head of the section.

According to an embodiment of the present invention, the hydrodynamic head obtained by the hydrodynamic head calculating unit 120 is obtained by applying the maximum water pressure measured in a preset night time zone.

According to an embodiment of the present invention, when the leak section detecting unit 140 estimates the leak section, the amount of change in the dynamic head of the sections continuously connected to at least one of the upstream and downstream sides of the leak section is within a predetermined range. It is estimated as a leaking section when the condition of having a deviation within the

이고, 타측 절점에서 검출한 누수음 강도가

이고, 누수 구간의 관로 길이가

일 시에,

의 누수음 강도가 검출된 일측 절점에서 누수 위치까지의 거리

을

으로 산정하여 누수 위치를 탐지한다.According to an embodiment of the present invention, the measurement unit 10 includes a water leak sound sensor 12 for detecting a water leak sound propagating through a pipe, and the water leak detection unit 100 includes the water leak section detection unit 140 ), the leak location estimator 150 for estimating the location of the leak according to the intensity of the leak sound detected at both nodes of the leak section estimated in );

, and the leak sound intensity detected at the other node is

and the pipe length of the leaking section is

at one time,

The distance from the leaking location at one node where the leak sound intensity of

second

to detect the leak location.

According to an embodiment of the present invention, the leak detection unit 100 estimates the leak section estimated by the leak section detection section 140 and the adjacent section connected to the inflection point as a boundary by the leak section detector 140 . For the extended section obtained by combining with the leaking section, the leak location is estimated according to the leak sound intensity detected at both nodes of the extended section, and the leaking section is corrected when the leaking location is estimated within the adjacent section.

In order to achieve the above object, the present invention provides a leak detection method based on hydrodynamic head analysis that detects a leak according to the water pressure measured by the water pressure sensor 11 in the measuring unit 10 installed along the pipeline in the equal water pressure zone 2, respectively. In the present, the hydraulic head calculating step (S10) of calculating the dynamic head for each node with the position head for each node using the water pressure measurement position by the measuring unit 10 as the node, and the pressure head according to the measured water pressure; A dynamic head change amount calculation step of calculating the dynamic head change amount between both nodes of the section for each section divided by nodes (S20); a water leakage area selection step (S30) of selecting an equal water pressure area (2) in which the distribution of the hydrostatic head calculated for each node is out of a preset range as a water leak suspicious area; Within the uniform water pressure zone (2) selected as the leak-suspicious zone, the inflection point is selected as the node with the largest change in dynamic head change, and then the section following the inflection point with a relatively large change in hydrodynamic head is estimated as the leaking section. detection step (S40); includes.

이고, 타측 절점에서 검출한 누수음 강도가

이고, 누수 구간의 관로 길이가

일 시에,

의 누수음 강도가 검출된 일측 절점에서 누수 위치까지의 거리

을

으로 산정하여 누수 위치를 탐지한다.According to an embodiment of the present invention, the measurement unit 10 includes a leak sound sensor 12 for detecting a leak sound propagating through a pipe, and the amount of the leak section estimated in the leak section detection step (S40). A leak location detection step (S50) of estimating the leak location according to the intensity of the leak sound detected at the node (S50);

, and the leak sound intensity detected at the other node is

and the pipe length of the leaking section is

at one time,

The distance from the leaking location at one node where the leak sound intensity of

second

to detect the leak location.

According to an embodiment of the present invention, the leak section estimated in the leak section detection step (S40) and the adjacent section connected with the inflection point as a boundary are combined with the leak section estimated in the leak section detection step (S40) in the extended section obtained For, the leak location verification step (S60) of estimating the leak location according to the leak sound intensity detected at both nodes of the extended section, and correcting the leaking section when the leak location is estimated within the adjacent section (S60); is performed.

The present invention selects an area where a leak occurs by comparatively comparatively analyzing the hydrodynamic head change for each section of the equal water pressure area, and detects a leak section within the selected area, so that it is possible to easily and conveniently detect a leak suspicious section without omission, It can be detected according to the water pressure measurement result without pipe network analysis using pipe network data, so any pipe network can be used universally and has the advantage of easy system construction.

According to an embodiment of the present invention, in detecting the location of the water leak in the water leak section by the water leak detection method, the location of the water leak is detected using the amount of attenuation in the intensity of the water leak according to the propagation distance of the water leak. can detect

1 is a block diagram of a leak detection system based on hydrodynamic analysis according to an embodiment of the present invention.
Figure 2 is a pipe network diagram illustrating the installation position of the equalized water pressure zone (2) and the measuring unit (10) of the dendritic pipe (1).
Figure 3 is a pipe network diagram illustrating the installation position of the equalized water pressure zone (2) and the measuring unit (10) of the grid-type pipeline (1).
4 is an exemplary view of a hydraulic gradient line (HGL) showing the amount of change in hydraulic head for each section in the equalized hydraulic pressure zone 2 before and after the water leak.
5 is a diagram illustrating a hydrostatic inclination line according to the leak location of the leaking section.
6 is a view for explaining a method of detecting the location of the leak in the leak section.
7 is a view for explaining a method of correcting the leaking section by determining the estimation error of the leaking section.
8 is a flowchart of a leak detection method based on hydrodynamic analysis according to an embodiment of the present invention.

The present invention divides the section by using the position where the water pressure is measured for the water supply pipe as the node, and calculates the dynamic head of each node according to the water pressure measured for each node and the ground height measured in advance for each node. The leakage section is detected by monitoring the change in the hydrodynamic head caused by the flow rate change.

However, since the dynamic head on the water supply pipe is affected by the amount of water supply, it is difficult to determine an absolute standard value to compare with the change in the dynamic head due to water leakage. Determining whether there is a leak, and estimating the leak section in the equal water pressure area determined as a leak.

Here, the uniform water pressure zone is defined as a zone in which the pipe network is configured so that the water pressure at each location has a value within a certain range. Accordingly, the dynamic head (or hydraulic pressure) obtained by adding the pressure head according to the water pressure and the position head according to the ground height also has a value within a certain range within the uniform water pressure zone. In such a uniform water pressure zone, the water pressure in the zone is managed within a certain range by artificially pressurizing or reducing the water pressure in the injection pipe according to the ground level of the zone, the distance from the drainage basin, etc.

Hereinafter, specific and various examples are shown and described so that those of ordinary skill in the art to which the present invention pertains can easily carry out the embodiments of the present invention with reference to the accompanying drawings. However, since it is also clear that the embodiments of the present invention can be practiced through various changes or modifications within the scope of the present invention, it is not limited to the described embodiments. Further, the embodiments of the present invention will not be described in detail because well-known configurations, functions, methods, and typical details can be implemented by those of ordinary skill in the art to which the present invention pertains.

Referring to the configuration diagram of FIG. 1 , the leak detection system based on hydrodynamic head analysis according to an embodiment of the present invention includes a measurement unit 10 installed at intervals along a pipe line 1 in an equal water pressure area 2 , and a measurement unit It includes a leak detection unit 100 for estimating a leak section and a leak location after determining whether there is a leak in the equal water pressure zone (2) according to the measured value of (10).

The measuring unit 10 includes a water pressure sensor 11 for measuring water pressure in the installed pipe line 1, a water leak sound sensor 12 for detecting a water leak sound propagating through the pipe line 1, and the water leak detection unit ( 100) and a communication module 13 to communicate with, and a controller 14 for performing a measurement operation of transmitting the measured water pressure and the detected water leak sound level to the water leak detection unit 100 through the communication module 13; It includes a power supply 15 to supply power necessary for the measurement operation.

Although not shown in detail in FIG. 1, the water pressure sensor 11 and the water leak sound sensor 12 may be installed in the pipeline 1 in a variety of known ways, and the communication module 13 is, for example, NB-IoT communication to communicate with the leak detection unit 100, the controller 14 generates and transmits data matching the measurement value with the measurement time, as well as time-series data obtained by real-time measurement for a certain period of time It can also have a data logger function that accumulates, stores, and then transmits, and the power source 15 may be composed of, for example, a battery, so a further detailed description will be omitted.

The water leak detection unit 100 collects the water pressure and the water leakage sound level measured and transmitted by a plurality of measurement units 10 installed in the pipeline 1, and then sets the same hydraulic head calculated according to the water pressure and the ground height to the equal water pressure area (2) The unit is analyzed to determine whether there is a leak, and the leak section is estimated, and the location of the leak in the leak section is estimated by analyzing the leak sound level. For this, the water leak detection unit 100 includes a data storage unit 110 , a dynamic head calculation unit 120 , a dynamic head change amount calculation unit 130 , a water leakage section detection unit 140 , and a water leakage location estimation unit 150 . include

In the storage unit 110, information grouping the plurality of measurement units 10 for each equal water pressure zone 2, pipe network system diagram information, the pipe length of each section divided by nodes, and the measurement unit 10 The position head for each node and the normal dynamic head range are stored using the position where the water pressure is measured as the node.

For grouping information of the measurement unit 10, refer to the pipe network diagram of the dendritic pipe 1 of FIG. 2 and the grid type pipe 1 of FIG. and explain

First, the pipe network diagram of the dendritic pipe (1) shown in FIG. 2 is a small block (1-3) composed of a dendritic pipe network by branching the drainage pipe (1-2) from the drainage main pipe (1-1) connected to the reservoir (4) It is a diagram exemplifying the pipe network of the medium block to be supplied with water. In general, for pipe network operation, in the main drainage pipe (1-1) and the drainage branch pipe (1-2), the flow rate is measured with a flow meter (5) to monitor the flow rate, and it is possible to detect a small block of leakage according to the flow rate change, It can also be used to detect water leaks by measuring water pressure with a hydrometer.

Among the small blocks (1-3), there may be some in which the water pressure control means (3) is installed in the drain pipe (1-2) according to the ground height. Here, the water pressure regulating means 3 may be a pressurization field operating a pump to increase the water pressure, or may be a pressure reducing valve installed to lower the water pressure. Although evenly managed within a certain range, there may be a pressure difference between the small blocks (1-3).

Accordingly, when the present invention is applied to the pipe network diagram illustrated in FIG. 2 , the equal water pressure zone 2 can be determined to be divided into small blocks, and the measurement unit 10 is installed in each small block along the pipe. On the other hand, although not shown, when the water pressure regulating means 3 is installed in the small blocks 1-3, the small blocks 1-3 are divided by the water pressure regulating means 3 as a boundary, and the equal water pressure zone 2 ) can be determined.

The installed measuring unit 10 divides and groups by equal water pressure area 2 according to the installation location, and stores grouping information matched for each equal water pressure area 2 in the data storage unit 110 .

In addition, as pipe network data, information on the pipe length of each section of the pipe line 1 divided by the location where the measurement unit 10 is installed as a node, and system diagram information indicating the connection state of each section are stored.

Since the pipe network diagram illustrated in FIG. 3 has a difference in that the pipe network in the small blocks 1-3 is composed of the grid-type pipe 1, the determination method of the equal water pressure zone 2 can be the same. However, the section of the pipeline (1) between the nodes determined according to the installation location of the measurement unit (10) also includes a pipeline (1) that is piped in parallel, so that the system diagram information and section pipe length include the paths of the pipes connected in parallel, respectively. Save it.

The position head stored for each node is a value determined according to the ground height of the position where the water pressure is measured by the water pressure sensor 11, Save it.

The normal hydraulic head range is the hydraulic head range when no leakage occurs, and it is a value that is predetermined and stored for each equal water pressure zone (2). It will be described in detail.

Hereinafter, according to the information stored in the data storage unit 110 and the measurement value of the measurement unit 10, a component for detecting a leak position in a water leak suspicious area, a water leak suspicious section in the equal water pressure area, and a water leak suspicious section First, a basic background theory used in the present invention and a method of detecting a leak based on the background theory in the present invention will be described with reference to FIG. 4 .

Since there is no water pressure regulating means 3 in the equal water pressure zone 2, Bernoulli's equation is as follows.

는 유속

와 중력가속도

로 산출되는 속도 수두이고,

는 수압(압력)

와 단위중량

로 산출되는 압력 수두이고,

는 지반고로 얻는 위치 수두이고, 아래첨자 1과 2는 절점을 구분하는 첨자이며,

은 양 절점 사이의 구간에서 발생하는 손실수두로서 대표적으로 아래의 수학식 2의 Darcy-Weisbach식으로 표현되는 마찰손실수두가 있다.here,

is the flow rate

and gravitational acceleration

is the velocity head calculated by

is the water pressure (pressure)

and unit weight

is the pressure head calculated by

is the position head obtained by the ground elevation, subscripts 1 and 2 are the subscripts separating the nodes,

is the head of loss occurring in the section between the two nodes, and there is the head of friction loss, which is typically expressed by the Darcy-Weisbach equation in Equation 2 below.

Here, f is the friction loss coefficient, u is the flow velocity, g is the gravitational acceleration, L is the length of the pipe, and D is the inner diameter of the pipe.

와 압력수두

의 합으로 표현되고, 수평 기준면에서 연직방향으로 나타낸 각 절점의 동수두를 연결한 선을 동수경사선(HGL : Hydraulic grade line)이라 한다.And, the dynamic head (H) of both nodes is the position head as shown in Equation 3 and FIG. 4(a) below.

and pressure head

The line connecting the hydraulic head of each node expressed in the vertical direction from the horizontal reference plane is called the hydraulic grade line (HGL).

As can be seen from Equations 1 and 2, the hydraulic head or hydraulic inclination line of each node is not constant because it is affected by the water flow rate.

As mentioned in advance, in the embodiment of the present invention, the above-mentioned normal hydrodynamic head range is obtained at each node of the equal water pressure zone 2 in the night time zone (for example, 03:00 to 04:00 AM) with a small amount of water supply. Set in advance to the range of the expected hydrodynamic head. For example, the friction loss coefficient can be used as the expected average value according to experience, and it can be set to a value within an appropriate range in consideration of the section length and pipe inner diameter, and the amount of water supplied at night time.

The amount of hydrodynamic change (ΔH) expressed as the difference in hydraulic head occurring in the section between both nodes is as shown in Equation 3 below.

Here, the amount of change in the dynamic head of each node or in the section between the nodes can be used to estimate the flow direction of water and the flow rate in each section.

The hydraulic inclination is the slope of the hydraulic inclination line, and it is expressed as the amount of change in the hydraulic head per section length. Accordingly, the flow rate can be estimated more accurately by using the hydraulic inclination than when using the dynamic head change.

However, in order to accurately estimate the flow rate in each section, it is necessary to know all of the pipe network data (the friction loss coefficient, length, and inner diameter of the pipe), and complex pipe network analysis is required. Therefore, it is difficult to use it to detect leaks.

On the other hand, in the present invention, by directly analyzing the dynamic head (H), it is determined whether there is leakage without estimating the flow rate and the leakage section is estimated.

Specifically, the pipeline of the equal water pressure zone 2 is constructed to have water pressure within a certain range even if there is a difference in ground height along the route of the pipeline, as illustrated in FIG. 4(a), and accordingly, the The value also has a value within a certain range, and the deviation of the dynamic head (H) of each node is very small, especially at night time when the amount of water supply is very small.

However, as illustrated in FIG. 4(b), when a leaking section occurs within the equal water pressure zone, the loss head increases by the amount of increase in the flow rate due to the leak, so the change in the dynamic head in the leaking section increases in proportion to the increase in the head loss, Moreover, as the hydraulic head is decreased due to the decrease in water pressure on the downstream side of the leaking section, the deviation of the dynamic head change obtained for each section as well as the dynamic head of each node increases.

At this time, the deviation of the dynamic head of the node and the variation of the dynamic head of the section clearly occurs during the night time when the amount of water supply is small, and, in particular, occurs more clearly at the time when the water pressure is the greatest due to the small amount of water supplied during the night time.

In addition, when there is a downstream section of the leaking section, the dynamic head in the downstream section changes more gently than in the leaking section. That is, when a leak occurs, the amount of change in dynamic head varies greatly at the first node after the leaking section as it affects not only the leaking section but also the amount of change in the hydrodynamic head in the downstream section. If there is an upstream section of the leaking section, the hydrodynamic head may gradually increase toward the upstream side.

Accordingly, the present invention detects a water leak by analyzing a change when a water leak section occurs within the equal water pressure area.

Hereinafter, leak detection using the hydraulic head deviation of the node and the deviation of the dynamic head change in the section, which occur according to the leak, and the leak location detection using the leak sound level will be described.

The dynamic head calculation unit 120 calculates the pressure head of each node by collecting the water pressure at each node measured by the measuring unit 10, and adds the pressure head and the position head for each node to obtain the dynamic head of each node. .

It is recommended to apply the pressure head calculated by applying the maximum water pressure measured in the preset night time for the obtained dynamic head. The preset night time zone is a time zone with relatively little water use. For example, it can be set from 03:00 to 04:00 AM, and the pressure head is calculated using the maximum water pressure value among the water pressures measured during this time and applied to the dynamic head calculation. can do. By applying the water pressure value when the water pressure measured at each node in the equal water pressure area becomes the maximum at the same time, it is good to obtain a dynamic head corresponding to the water pressure value at the time when the water flow rate is the minimum in each section within the equal water pressure area. Accordingly, the measurement timing of the water pressure applied to each equal water pressure zone may be different.

The hydrodynamic change amount calculating unit 130 calculates the hydrodynamic head change amount between both nodes of the section for each section divided by the nodes. That is, the amount of change in the hydraulic head for each section is the difference between the hydraulic head obtained for both nodes of the section.

In the embodiment of the present invention, since the section length is stored, the amount of change in hydraulic head for each section can be used instead of the hydraulic slope obtained by using the difference in the dynamic head of both nodes of the section and the pipe length of the section. In other words, since the difference in dynamic head is affected by the pipe length of the section when water flows, when the section length is known, the hydraulic inclination calculated as the value of the difference in the hydraulic head compared to the pipe length rather than the difference in the dynamic head is used as the amount of change in the dynamic head. it's good

The leak section detection unit 140 includes a water leak area estimating unit 141 for selecting an equal water pressure area suspected of leaking, and a water leak area for estimating a section suspected of leaking within an equal water pressure area selected as an area suspected of leaking water. and an estimator 142 .

As illustrated in FIGS. 2 and 3 , the water leakage area estimating unit 141 includes a preset normal hydraulic head stored in the data storage unit 110 in which the distribution of the hydrodynamic head calculated for each node among the plurality of uniform hydraulic pressure zones 2 is stored in the data storage unit 110 . Select the water-leakage suspicious area (2) outside the range.

As an embodiment, if the minimum and maximum values of the hydraulic head for each node are not within the normal hydraulic head range, a leak-suspected area is selected.

As an embodiment, by grouping the hydraulic head values for each node in the order of magnitude, an equal water pressure area in which the difference between the average values for each group is out of the normal hydrodynamic head range is selected as a leak suspect area. That is, since the hydrodynamic head of the node in one direction (ie, the downstream direction) with the boundary of the section in which the water leak occurs may change gently, it is possible to select a suspected leak area by reflecting this well.

As a modified embodiment, an even water pressure area in which the distribution of the amount of change in the hydrodynamic head calculated for each section is out of a preset range may be selected as a water leak suspicious area. That is, as an embodiment, by presetting the maximum amount of change in hydrohead head in a steady state in which leakage does not occur, an area in which the amount of change in dynamic head in a section greater than the amount of change in dynamic head in the maximum section may be selected as the suspected leak area. As an embodiment, by presetting a deviation in the amount of change in hydrodynamic head in a normal state without water leakage, an equal water pressure area in which the amount of change in hydraulic water out of the preset deviation occurs may be selected as a suspected water leak area.

The leakage section estimating unit 142 calculates the variation in the amount of change in the amount of change in the dynamic head between the sections connected to the node for each node in the uniform water pressure area 2 selected as the water leak suspicious area, and then the amount of change in the hydraulic head fluctuates the most A node is extracted and selected as an inflection point, and a section with a relatively large change in hydrodynamic head among sections following the selected inflection point is estimated as a leaking section.

When the hydraulic pressure is measured at the branching or merging point and determined as a node, the difference between the maximum and minimum values of the change in hydrodynamic head can be obtained as the change in the amount of change in the dynamic head at the node. A large section can be estimated as a leak section.

On the other hand, since the hydrostatic slope occurs in various patterns depending on the location of the section where the leaking section occurs, the result of pattern analysis can be reflected in the estimation of the leaking section.

5 is a view illustrating the change of the hydraulic inclination line according to the location of the leaking section.

As described with reference to FIG. 4(b), since the amount of change in section dynamic head varies the most at the first node (water pressure measurement location) on the downstream side pipe at the location where the water leak occurs, the amount of change in section dynamic head as illustrated in FIG. 5 This largest point is chosen as the inflection point.

Exceptionally, if the amount of hydrodynamic change in the section at the downstream end is the largest, the end node is selected as the inflection point. It can be programmed to estimate leaks.

If there is a downstream section leading to the leaking section, the dynamic water head at each node shows a generally gradual decrease in the downstream pipe starting from the inflection point, and appears to be almost the same value if there is no use of water downstream. That is, the meaning of the inflection point here means the maximum inclination transition point at which the dynamic head decreases rapidly and then changes rapidly to change into a gradual decreasing trend. Accordingly, there is a deviation within a predetermined range between sections of the downstream conduit.

If there is an upstream section following the leaking section, the flow rate of the leak also flows in the upstream pipe and affects the dynamic head, so the dynamic head of the node shows a tendency to gradually increase toward the upstream side. Accordingly, there is a deviation within a predetermined range even between sections of the downstream conduit.

Therefore, since the estimated leakage section is connected to at least one of the upstream pipe and the downstream pipe, when the condition that the hydraulic head change (ΔH) obtained in the sections of the connected pipe meets the condition that the deviation within a predetermined range is satisfied In the estimated leak interval, it can be determined that the leak probability is relatively high. That is, the leakage probability is evaluated differently according to the deviation of the change amount (ΔH) of the hydraulic head of the contiguous pipeline. In particular, it is better to give a higher probability when the downstream conduit shows a deviation of the hydrodynamic change amount (ΔH) within a predetermined range.

The leak location in the water leak section estimated as described above is detected by the leak location estimation unit 150 .

The leak location estimating unit 150 detects the leak location according to the strength at which the leak sound generated at the leak location in the leak section is attenuated while reaching both nodes. is substituted into Equation 5 below to estimate the leak location.

은 양 절점 중에 일측 절점에서 검출한 누수음 강도이고,

는 양 절점 중에 타측 절점에서 검출한 누수음 강도이고,

은 누수 구간의 관로 길이이고,

은

의 누수음 강도가 검출된 일측 절점부터 누수 위치까지의 거리이다. 6, in Equation 5

is the leak sound intensity detected at one node among both nodes,

is the leak sound intensity detected at the other node among both nodes,

is the pipe length of the leaking section,

silver

is the distance from the leaky location to the leaky sound intensity from the detected one side node.

The intensity of the leak sound generated at the leak point of the leak section is attenuated in inverse proportion to the propagation distance when propagated toward both nodes of the leak section. Based on the inverse relationship between the leak sound intensity and the propagation distance, Equation 5 above can be obtained

도 아래의 수학식 6으로 얻을 수 있다.In addition, the distance from the other node to the leak location

It can be obtained by Equation 6 below.

On the other hand, since leak sound is generally a high-frequency band, it is better to obtain the leak sound as time-series data at both nodes, then frequency-convert the leak sound data to determine an average value of the sound in the high-frequency band as the leak sound intensity. Here, for the high frequency band, an experience value for the frequency band of the leak sound may be applied. As another example, after frequency analysis of leak sound data measured at both nodes, a leak sound can be obtained by extracting the corresponding frequency components. However, the present invention is not limited thereto, and a known technique for extracting a leak sound while removing noise in a situation in which noise other than a leak sound is introduced may be applied, and a detailed description thereof will be omitted.

However, as illustrated in FIG. 7 , when the leak location is near the inflection point and occurs in the section adjacent to the leaking section estimated above, an error in estimation of the leaking section may occur. That is, as illustrated in FIG. 7 , if the section distance to the first node on the upstream side of the leaking location is short and the head loss in that section is also small, the first node on the upstream side may be mistaken for an inflection point.

Accordingly, as shown in FIG. 7 , the leak detection unit 100 expands the detection section of the leak location by adding the leak section estimated above and the section adjacent to the inflection point as the boundary with the leak section estimated above. That is, a leak position is obtained by substituting the leak sound intensity obtained at both nodes of the extension section into Equation 5 or Equation 6 above.

If the leak location obtained at this time belongs to the leaking section, the leaking section is determined and the leaking location is also confirmed. On the other hand, if the leak location belongs to the adjacent section, the adjacent section is corrected to the leaking section, and the leak location is corrected to the location of the adjacent section.

For re-verification, the leak location estimated by substituting the leak sound intensity obtained from both nodes of the adjacent section into Equation 5 or Equation 6 is compared with the leak location obtained in the extension section, and then the leak location may be re-corrected. . In the re-verification process, the leak location can be corrected by using the average of both leak locations or by defining the range of the leak location as a section between the two leak locations.

On the other hand, since outdoor fire hydrants are sometimes installed in pipelines buried along roads at intervals, the measuring unit 10 is fastened to the outlet of the outdoor fire hydrant to block the leakage of water flowing into the outdoor fire hydrant and measure the water pressure of the flowing water And it is possible to detect the leaking sound that propagates in the pipeline and reaches the outdoor fire hydrant. Since the structure of the measurement unit 10 for installation in an outdoor fire hydrant is a known technique, a detailed description will be given.

In this way, when the measuring unit 10 is installed in the outdoor fire hydrant, the water leakage section can be estimated among the sections between the outdoor fire hydrants by using the location where the outdoor fire hydrant is installed as a node, and the water leakage location can also be estimated.

As a modified embodiment, the present invention can also be applied to a fire hydrant facility including a water supply line (pipe line) installed with a fire hydrant at intervals in the fire fighting facility, and a pressurized pump for supplying fire water to the water supply line. That is, the measuring unit 10 is installed in each fire hydrant, the above-mentioned related information is stored in the data storage unit 110, and the leakage section is estimated according to the measured water pressure and the leak sound level, and the leak location is detected. can do. In this case, when the hydrant is not in use, there is no flow, so the dynamic head of each node is almost the same. Accordingly, since the hydrodynamic head change is clearly shown when a leak occurs, the leak section can be accurately detected.

8 is a flowchart of a leak detection method based on hydrodynamic analysis according to an embodiment of the present invention.

The leak detection method based on the hydrodynamic head analysis is based on the water pressure measured by the water pressure sensor 11 in the measuring unit 10 installed along the pipeline in the equal water pressure area, and the water pressure measurement position by the measuring unit 10 as the node is the leak in the section. As the detection method, since it is performed by the leak detection system based on the hydrodynamic analysis described above, the redundant detailed description will be omitted and the main technical contents will be mainly described.

The leak detection method based on the dynamic head analysis according to an embodiment of the present invention includes the steps of calculating the hydrostatic water by the hydrodynamic calculation unit 120 ( S10 ) and calculating the amount of change in the dynamic head by the dynamic head change calculation unit 130 . (S20), the leak area selection step 30 and the leak section detection step (S40) by the leak section detection unit 140, and the leak location detection step (S50) by the water leak location detection unit 150, and It includes a leak location verification step (S60).

The dynamic head calculation step (S10) is to calculate the pressure head for each node by collecting the water pressure measured at each node in the equal water pressure area, and then add the previously investigated position head for each node to the pressure head to calculate the dynamic head for each node. . In this case, it is recommended to use a value obtained by applying the maximum water pressure measured in the preset night time for the pressure head.

In the step S20 of calculating the amount of change in dynamic head, for each section, the difference in hydraulic head obtained from both nodes of the section or the hydraulic inclination is calculated to obtain the amount of change in the dynamic head of the section. Here, the hydraulic slope is obtained by dividing the hydraulic head difference between the nodes of the section by the pipe length of the section.

In the water leakage zone selection step (S30), it is determined whether water leaks in the uniform water pressure zone by analyzing the dynamic head distribution or the dynamic head change amount distribution. That is, an equal water pressure area in which the distribution of the dynamic head calculated for each node is outside the preset range is selected as a leak suspect area, or an equal water pressure area in which the distribution of the dynamic head change calculated for each section is out of the preset range is designated as a leak suspect area. select

In the leak section detection step (S40), after selecting the inflection point of the hydrostatic head change within the uniform water pressure area selected as the leak suspicious area, the section having a relatively large dynamic head change among the sections following the inflection point is estimated as the leaking section. Here, the inflection point is selected as the node where the amount of change in the hydrodynamic head fluctuates the most. When estimating the leaking section, add a condition in which the amount of change in the dynamic head of the sections continuously connected to at least one of the upstream and downstream sides of the leaking section has a deviation within a predetermined range, and when the condition is satisfied, select

In the leak location detection step (S50), among the leak sounds detected by the leak sound sensor 12 of the measuring unit 10, the leak location in the leak section is estimated according to the strength of the leak sound detected at both nodes of the leak section. . Here, the leak location uses Equation 5 or 6 by using the phenomenon in which the leak sound intensity decreases in inverse proportion to the propagation distance.

The leak location verification step (S60) extends the leak section by adding the leak section estimated in the leak section detection step (S40) and the adjacent section connected by the inflection point as a boundary, and then detected at both nodes of the expanded leak section. Estimate the leak location based on the strength of the leak sound. At this time, if the estimated leak location is within the adjacent section, the leak section is corrected, and the modified leak location is also corrected to the leak location within the leak section. Here, Equation 5 or Equation 6 is also used for the leak location within the extended water leak section.

In the above, specific embodiments have been shown and described to illustrate the technical idea of the present invention, but the present invention is not limited to the same configuration and operation as the specific embodiments as described above, and various modifications are within the limits that do not depart from the scope of the present invention. can be carried out in Accordingly, such modifications should be considered to fall within the scope of the present invention, and the scope of the present invention should be determined by the following claims.

1 : Pipe line 1-1 : Drainage main pipe
1-2: drain pipe 1-3: small block
2: equalizing water pressure zone 3: water pressure control means
4: Reservoir 5: Flowmeter
10: measurement unit
11: water pressure sensor 12: water leak sensor
13: communication module 14: controller
15: power
100: leak detection unit
110: data storage unit
120: Dongsu head mountain range
130: dynamic head change amount calculation unit
140: leak section detection unit
141: leak area estimator 142: leak section estimator
150: leak location detection unit

Claims (15)

a plurality of measuring units 10 installed along the pipeline to measure water pressure with a water pressure sensor 11, respectively; and a water leak detection unit 100 for detecting a water leak in the equal water pressure zone 2;
The leak detection unit 100
a data storage unit 110 storing the position head for each node using the water pressure measurement position by the measurement unit 10 as the node;
a dynamic head calculating unit 120 for calculating the dynamic head for each node with the pressure head according to the measured water pressure and the stored position head;
a dynamic head change amount estimating unit 130 for calculating a dynamic head change amount between both nodes of the section for each section divided by nodes;
The uniform water pressure area (2), in which the distribution of dynamic head calculated for each node is outside the preset range, is selected as a leak suspect area, and within the uniform water pressure area (2) selected as the leak suspicious area, the change in the dynamic head fluctuates the most. After selecting a node as an inflection point, a leak section detection unit 140 for estimating a section having a relatively large amount of change in hydrodynamic head among sections following the inflection point as a leak section;
containing
A leak detection system based on hydrodynamic analysis. The method of claim 1,
The leak section detection unit 140 is
The distribution of the amount of change in the hydrodynamic head calculated for each section is out of the preset range, and the uniform water pressure area (2) is selected as a water leak suspect area.
A leak detection system based on hydrodynamic analysis. The method of claim 1,
The dynamic head change amount calculating unit 130 is
The hydraulic head difference between both nodes of the section and the hydraulic inclination obtained according to the pipe length of the section are applied as the amount of change in the dynamic head of the section.
A leak detection system based on hydrodynamic analysis. The method of claim 1,
The dynamic head obtained by the dynamic head calculating unit 120 is
obtained by applying the maximum water pressure measured at a preset night time
A leak detection system based on hydrodynamic analysis. The method of claim 1,
When estimating the leak section in the leak section detection unit 140,
Estimated as a leaking section when the condition of having a deviation within a predetermined range of dynamic head change in sections continuously connected to at least one of the upstream and downstream sides of the leak section is satisfied
A leak detection system based on hydrodynamic analysis. The method of claim 1,
The measurement unit 10 is
Includes a water leak sensor 12 for detecting a water leak sound propagating through a pipe,
The leak detection unit 100 is
A leak location estimator 150 for estimating a leak location according to the strength of the leak sound detected at both nodes of the leak section estimated by the leak section detection unit 140;
The leak sound intensity detected at one node is

, and the leak sound intensity detected at the other node is

and the pipe length of the leaking section is

at one time,

The distance from the leaking location at the one-side node where the leak sound intensity of

second

to detect the leak location by calculating
A leak detection system based on hydrodynamic analysis. 7. The method of claim 6,
The leak detection unit 100
For the extended section obtained by combining the leak section estimated by the leak section detection unit 140 and the adjacent section connected to the inflection point as a boundary with the leak section estimated by the leak section detecting section 140, it is detected at both nodes of the extension section By estimating the location of the leak according to the intensity of one leak, the leak section is corrected when the leak location is estimated within the adjacent section.
A leak detection system based on hydrodynamic analysis. In the leak detection method based on hydrodynamic head analysis for detecting water leakage according to the water pressure measured by the water pressure sensor 11 in the measuring unit 10 installed along the pipeline in the equal water pressure zone 2,
A dynamic head calculating step (S10) of calculating the dynamic head for each node with the position head for each node using the water pressure measurement position as the node by the measuring unit 10 and the pressure head according to the measured water pressure;
A dynamic head change amount calculation step of calculating the dynamic head change amount between both nodes of the section for each section divided by nodes (S20);
a water leakage area selection step (S30) of selecting an equal water pressure area (2) in which the distribution of the hydrostatic head calculated for each node is out of a preset range as a water leak suspicious area;
Within the uniform water pressure zone (2) selected as the leak-suspicious zone, the inflection point is selected as the node with the largest change in dynamic head change, and the section following the inflection point with a relatively large change in dynamic head is estimated as the leaking zone. detection step (S40);
containing
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The leak area selection step (S30) is
The distribution of the amount of change in the hydrodynamic head calculated for each section is out of the preset range, and the uniform water pressure area (2) is selected as a water leak suspect area.
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The dynamic head change amount calculation step (S20) is
The hydraulic head difference between both nodes of the section and the hydraulic inclination obtained according to the pipe length of the section are applied as the amount of change in the dynamic head of the section.
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The hydrodynamic head calculation step (S10) is
The hydraulic head is obtained by applying the maximum water pressure measured in the preset night time zone.
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The leak section detection step (S40) is
Estimated as a leaking section when the condition of having a deviation within a predetermined range of dynamic head change in sections continuously connected to at least one of the upstream and downstream sides of the leak section is satisfied
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The measuring unit 10 is fastened to the outlet of the fire hydrant installed at intervals in the pipeline to block the leakage of water flowing through the fire hydrant and measure the water pressure of the flowing water,
The leak section detection step (S40) is
Using the location where the fire hydrant is installed as the node, it is a method of estimating the leakage section among the sections between the fire hydrants.
A leak detection method based on hydrodynamic analysis. 9. The method of claim 8,
The measuring unit 10 includes a leak sound sensor 12 for detecting a leak sound propagating through a pipe,
A leak location detection step (S50) of estimating the leak location according to the strength of the leak sound detected at both nodes of the leak section estimated in the leak section detection step (S40);
The leak sound intensity detected at one node is

, and the leak sound intensity detected at the other node is

and the pipe length of the leaking section is

at one time,

The distance from the leaking location at one node where the leak sound intensity of

second

to detect the leak location by calculating
A leak detection method based on hydrodynamic analysis. 15. The method of claim 14,
For the extended section obtained by combining the leak section estimated in the leak section detection step (S40) and the adjacent section connected to the inflection point as a boundary with the leak section estimated in the leak section detection step (S40), detection at both nodes of the extension section A leak location verification step (S60) of estimating a leak location according to one leak sound intensity, and correcting a leak section when the leak location is estimated within an adjacent section (S60);
to do
A leak detection method based on hydrodynamic analysis.

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